Combustors are commonly used in industrial and power generation operations to ignite fuel to produce combustion gases having a high temperature and pressure. For example, gas turbines typically include one or more combustors to generate power or thrust. A typical gas turbine used to generate electrical power includes an axial compressor at the front, one or more combustors around the middle, and a turbine at the rear. Ambient air may be supplied to the compressor, and rotating blades and stationary vanes in the compressor progressively impart kinetic energy to the working fluid (air) to produce a compressed working fluid at a highly energized state. The compressed working fluid exits the compressor and flows through one or more nozzles into a combustion chamber in each combustor where the compressed working fluid mixes with fuel and ignites to generate combustion gases having a high temperature and pressure. The combustion gases expand in the turbine to produce work. For example, expansion of the combustion gases in the turbine may rotate a shaft connected to a generator to produce electricity.
Many combustor components are subject to high vibration environments which can lead to increased wear, cracking, premature failure, pressure oscillations, flow oscillations, or other undesirable effects. For example, combustor nozzles are often attached to an end cover at one end and extend toward the combustion chamber at the other end. Base excitation, working fluid or fuel perturbations, or any other source may produce natural frequencies or other forced frequencies in the nozzles that cause the nozzles to vibrate. The vibrations in turn may lead to detrimental wear, fatigue cracking, tones, or other undesirable effects in the combustor and/or downstream components. Design clearances between the nozzles and support structures that allow for thermal growth and manufacturing tolerances make it difficult to damp the vibrations. Therefore, an improved system and method for damping combustor nozzle vibrations would be useful.